A polarizing plate having a structure in which a polarizer and a retardation film are stacked may be used to prevent reflection of external light or ensure visibility in a display, for example, a liquid crystal display or an organic light emitting device.
Here, a retardation film is a ½ or ¼ wavelength retardation film depending on retardation characteristics. The ½ or ¼ wavelength retardation films which have been known so far exhibit retardation differences according to wavelengths, and therefore are operated in a limited range of wavelengths. For example, in many cases, a film serving as a ¼ wavelength retardation film with respect to light having a wavelength of 550 nm may not be operated with respect to light having a wavelength of 450 or 650 nm.